Sulphur sludge treatment



,Dec. 22, 1931. u SElL 1,837,493

SULPH UR SLUDGE TREATMENT Filed May '7, 1926 INV'ENT R I W n m 1131 ATTOR Eva liquid'hawing an iron compound" suspended the extractionof further quantities-of sludgepto v 5 which is caused to float as .a foam, :and to be 111g sulphur in suspension, which may be fil- 7 1.335 washing and the like.

r 340 bearing sludges when thereoover-y of=extrar Fig. Qis asimi-l'ar view of alternate apparas so Patented Dec. 22, 1931 i r a i i v UNITED ,PATENTd OFFICE GILBERT .E. suit, or .NEwAnK; NEW, annsnx', nss'reivoniromeson-Ens COMPANY,

or :errrsrnnon, PENNSYLVANIA, A .conronnrron or PENNSYLVANIA j SULPHUR sntrnons'rnnnrmnnr 5 Application filed May 7, 19'26.-- Serial 110. 107,521.

The present invention relates in general Suitable forfurther use,as for examp'le'iron to improvements in method and apparatus-sulphide. The invention has forfuritheraobtor treatment of sulphur-bearing sludge "for jeicts suchother improvementsandsuoh other the recovery or useful constituents thereof operatlve advantages or results as may be and more particularly to the recovery ofsultound'to obtain in the-processes or apparatus phur and soluble compounds, such as ferrohereinatter describedorelaimed. Q cyanide's, tromrsu-lphur-bearing sludges, priv ,Bme'fly-st ted, the present invention conmanily such sludges as maybe produced in slstsin subjecting the sludge to be treated processes for the removal of hydrogen -su lto the-action of ammonium sulphide vapor, 'qo phide and analogous impurities from fuel WhlCll condenses and,dissolvestheksulphur gases, for instance, those processes described content of thesaid sludge, and zreacts'with and claimedinUnitedStates Patent 1,578,560 more or less soluble compounds, as lor exof Frederick Sperr,-Jr., and in Patent of ample, sodium terro-terrocyanide, to form Frederick WV.- Sperr, J 11., and David L. Jaammonium .fer-rocyan'ide, 1wh'i'ch' is soluble 16 cobson, 1,656,881 granitedlanuary 17, 1928, thecondensedliquor of ammonium polyand applications of Frederick WV. 'Sperr, J12, sulphide; filtering the said liquor to remove Ser.Nos.:21,979:and21,983,tiled April9,1-925. insoluble compounds suchas iron sulphide; Briefly :stated, such processes consist in :suband heating the filtrate to precipitate suljecting the gas to contact with an alkaline phuran'd nevolat-ilize ammoniumsulphide tor therein,--re1no'ving said liquid from contact The products obtainedifrom suchtreatwith the gas, and subjecting it toaeration, 'ment' are, first, :a residue of; iron sulphide, thereby eflectingarejuvenation or revivifica- (or other insoluble sulphide) and second a tion thereof, and liberating the sulphur, solution ofammoniumferrocyanide,icontainremoved as such; The said foamv is usually tered to recover the sulphur. The filtrate concentrated to :a sludge,'filtered, wash-edan'd may then be concentrated to recover ammodried. The product resultant fro'insuch simniurn ferrocyanide. a a ple procedure contains, in addition to sul- In the accompanying drawings formingla 52 0 phur, insoluble matter, such-as iron oxide part loft-his specification and showing forso and/or sulphide, and soluble materials such purposes of exemplification apreferred apas sodium ferro-ierrocyanide and/or-;ferro-' paratus and. method in which the invention 7 cyanide, each or all of which are somewhat be embodied and practiced but without difficult to remove by ordinary methods of lmg the laimed inv ntion specifically to I suchillustrative instance or instances, In my co pencling applications for United Figure lisadiagrainmaticielevajtional view States Letters Patent, Serial Nos. 107,522 partly Vertical cross-section of apparatus (SF-SS) and 1O7,'5Q4EY(SWS'S), filed of even for-treating sulphur-bearing sludge in .ae. date, I have provided for treating sulphurcordance withnthe present invention; and

neoius mineral matterwas important, and tus, whereby the-treatment may be conducted when'therecovery ofranexceptionally pure Semiwontinuously. 1 I sulphur was transcendent, respectively; Y, The same characters of reference designate In my present invention, 1 provide means the same parts in each of the views of the 5 for recovering asubstantially pure sulphur r wings. w 7 1 1 V fromthesaidzsludge or othersimilar sulphur- Referring to the drawings, particularly bearing sludges, for recovering a substan- Fig l, 'betoue charging the'sulphur-bearing tialrly 'puresicle product, such as :a solution sludge into the apparatuait is preferable to V of .ammoniiuinferrocyanicle, aand'ior the re filter vand wash it-thoroughly; The, resulting i virc'overy; ofthe insoluble material a form cake residue:ispzdischarged-irom the filter" press, and is placed, preferably in a moist state, in the screen or basket 2, within the vessel 1, which vessel is provided with a water jacket 3 for cooling purposes, said jacket hav ing an inlet 21 and outlet 22, a removable top 4, a vapor inlet 5 that dips into the liquid in vessell, and outlets6 and 7. The vapor inlet conduit 5 communicates with the upper portion of thevaporizer 8, which is provided with a heatingrjacket ,10, for superheated steam or the like admitted at 23 and withdrawn at 24,-, and Vaporizer 8 is also provided with an inlet comprising theconduit 6 which leads the overflow from vessel 1' to'such .vaporizer, and such vaporizer isalso provided I with a 'drain'9. The processmay be set in action by introducing 'ammoniacal liquor or ammoniumsulphide or polysulphide solution -fer rocyanide.

into the vessel 8 and heating the same'to boiling. i The ammonia and/or ammonium sulphide is liberated'a's a vapor, and escapes with steam through the conduit 5 leading into the liquid in'the coldvessel 1, wherein it reacts with the sulphur to form ammonium polysulphide, which dissolves in the condensed liquid. The condensed solution also reacts upon any sodium ferro-ferro'cyanide and/or ferrocyanide, forming-ammonium ferrocyanide,which dissolves. The solution overflows through the sealed'conduit 6, and passes into the heated-vessel 8, where the heat causes precipitation of'free sulphur and volatilization of ammonium sulphide. The said vapor escapes with steam through conduit 5,: dissolves more sulphur in the vessel 1, and thus "acyclic operation commences. During the course of the process, excessvapors from the vessel 1 are led by excess vapor outlet '7 through the sealed condenser 11, to be condensed. The condensate may beireturned to the system. VVhendesired, the liquid, containing'precipitat'ed sulphur and dissolved ammonium ferrocyanide, is withdrawn through the drain 9, filtered to recover the said sulphur, and concentrated to recover the The porous screen 2 that serves to retain 'all theinsolublefma-terial, such asiron sulphide, present in'the sludge, 'is removed as convenient from the vessel 1 andthe retained material is removed therefrom.

v In accordance with the present invention, 1 may so constitute my apparatus as to achieve a semicontinuous' action, by providing, as

- shown more particularly in Fig. 2, alternate H filters 12a and 12b in place of the screen 2 Within the vessel 1.. ln this instance, by

opening valves 13 and 15, and closing valves 14 and 16; the sludge "and ammoniacal liquor are led by conduit 6 from vessel 1 to the filter 31 2 am which the sludge and ammoniacal liquor arepassed through the filter bed -a .for removal of iron sulphidef'When a con '"siderable quantity of insoluble material, such i ras iron sulphide, has collected on the filtering surface 20a, valves 13 and 15 are closed, valves 14 and 16 are opened, and the sludge is passed through the filter 12-b, while the sediment is removed from the filter 12-a, access to which is had through the opening 19a; The-filters 12(; and 12Z are operated'alternately as is convenientfl monium ferrocyanide and insoluble iron compound from material containin sulphur, ferrocyamd'e and-1ron compoun which comprises: reactmg on said material with an extracting solution of ammonium sulphide in an extractor to. dissolve the sulphur and to dissolve soluble cyanides as ammonium ferrocyanide; withdrawing and filtering a portion ofthe extracting solution from the extractor to separate insoluble iron compounds therefrom; heating the withdrawn Insuch semi-continuous operation, I also and filtered solution to volatilize ammonium sulphide and precipitate free sulphur there- 7 from; returning the vapors ofammoniuin sulphide to the extractor for further dis solving of sulphur; and condensing the va-- pors in the extracting solution in theextractor itself. w

2. A process for obtaining pure sulphur and substantially pure soluble cyanide compounds and a substancewhichliberatesfree sulphur -on oxidation. from material contain- "ing sulphur, cyanide compounds and. substances which liberate free sulphur on oxidationof the sulphide thereof which comprises reacting on-such" material with an extracting-solution in anextractor to dissolve sulphur and to dissolve soluble cyanide compounds;

withdrawing and-filtering a portion of the extracting solution from the extractor 'to separate therefrom as an insolubleso much asmay be present of said substance which liberates free sulphur on oxidation ofv the sulphide thereof; heating the withdrawn and filtered extracting solution to volatilize the sulphur dissolvingmedium thereof and precipitate free sulphur therefrom; returningthe :vapors of the dissolving medium'to the ex tractor for further d'issolving of sulphur,

and condensing said vapors in the extractingsolution in the extractor itself;

3; A process 'for obtaining substantially pure sulphur and 1a substance'which liberates free sulphuron oxidation of the sulphide thereof from material containing the same,

which comprises: reacting on said material with a sulphur extracting solution inv an extractor to dissolve sulphur; withdrawing and filtering a portion of the extracting solution from the extractor to separate as an insoluble from said portion so much of the said substance which liberates free sulphur on oxidation of the sulphide thereof; heating the withdrawn and filtered portion of the extracting solution to volatilize the dissolving medium and precipitate free sulphur; returning the vapors of the dissolving medium to the extractor for further dissolving of sulphur; and condensing said vapors in the extracting solution in the ex-.

tractor itself.

4. A method for obtaining substantially pure sulphur from material containing sulphur, which comprises: extracting sulphur from said material with an extracting solu- 2 tion in an extractor to vdissolve sulphur; withdrawing from the extractor a portion ofthe extracting solution containing extracted sulphur and filtering it; heating the withdrawn and filtered portion of the extracting solution to volatilize the sulphur dissolving medium and precipitate free sulphur; returning the vapors to the extractor for further dissolving of sulphur; and condensing said vapors in the extracting solution in the extractor itself.

5. A method for obtaining substantially pure sulphur from material containing sulphur, which .comprises: extracting sulphur from said material with an extracting solution in an extractor to dissolve sulphur; withdrawing from the extractor a portion of the extracting solution containing extracted sulphur; heating the withdrawn portion of the extracting solution to volatilize the 40 sulphur dissolving medium and precipitate free sulphur; returning the vapors to the extractor for further dissolving of sulphur; and condensing said vapors in the extracting solution in the extractor itself.

6. A method for obtaining substantially pure sulphur from material containing sulphur, which comprises extracting sulphur from said material with an extracting solution of ammonium sulphide in an extractor to dissolve sulphur; withdrawing from the extractor a portion of the extracting solution containing extracted sulphur; heating the withdrawn portion of the extracting solution to volatilize ammonium sulphide and precipitate free sulphur; returning the va pors to the extractor for further extraction of sulphur; and condensing said vapors in th]ef extracting solution in the extractor itse- 7 on In testimony whereof I have hereunto set my hand. 1

GILBERT E. SEIL. 

